Modbus Interface manual
LMC341 DIWE
Page 9
6.2. Data values, scaling and data
types
Following is a description of used scaling and data types.
Scale 1, 10 and 100 refers to where the decimal point
is implied, as a decimal value can’t be transmitted via
Modbus.
Scale 1:
The value is the exact value
Scale 10:
To transmit a value it must be multiplied
by 10; i.e. 12.3 -> 123
A received value must be divided by 10;
i.e. 123 -> 12.3
Scale 100:
To transmit a value it must be multiplied
by 100; i.e. 1.23 -> 123
A received value must be divided by 100;
i.e. 123 -> 1.23
uint8:
Unsigned 8-bit integer
uint16:
Unsigned 16-bit integer
sint16:
Signed 16-bit integer
uint32:
Unsigned 32-bit integer
sint32:
Signed 32-bit integer
6.3. Modbus function codes
Function
Code
(hexadecimal)
Code
(decimal)
Read Holding Registers
03
03
Read Input Register
04
04
Read/Write Multiple Registers
17
23
6.4. Modbus exception codes
Code
Name
Meaning
01
Illegal function
The function code is not valid.
02
Illegal data address
The specified register is not valid
03
Illegal data value
The value is not allowed
